Bolt-threader



2 Sheets--Sheet I.

2.23 l. R W W xg N (No Model.)

L. KIRCHENBAUER.

BOLIl THRBADER.

Patented Nov. 21, 1893.

(No Model.) 2 sheetssheet 2. L. KIRCHENBAUBR. BOLT THRBADBR Patented Nov. 21; 1893.

UNITED STATES PATENT union.

`LOUIS' KIROHENBAUER, OF OHIOAGO, ILLINOIS.

SPECIFICATION `rainning part ofIiettrs I'Patent No. 509,039, dated ivoyemtetv 21, i893.

' iippii'ctnot ined April' zell 1893?Y To a/ZZ whom it may concern:

vBe it known that I, LOUIS KIROHENBAUER, a citizen of the UnitedStates, residing at Chik cago, in the county of Cook and State of Illi- A 5 nois, have invented certain new and useful Improvements in Bolt-Threaders, of whichY the following isa full, clear, and exact deinvention relates more particularly to such' i 5 appliances as are designed for use upon'turret-lathes, in which the dies or cutters are' maintained in stationary condition while the object to be threaded is rotated. l

Among the primary Objects of my invenzo tion is included that of producing thread-cutting appliances which shall automatically cut screw-threads of any desiredvlength and depth,

and which at the completion of the threadcutting action, shall automatically release the object which has been''operat'ed upon; furthermore, to produce a thread-cutter which shall be simple, strong and durable in its con-l struction, and accurate and reliable in its operation, and the parts of which shall be capable of ready adjustment to accord with difterent sizes and lengths of screwfthreads, and the parts of which shall also be free from all liability of derangement.

To 'the above purposes, my invention con- 3 5 sists in certain peculiar and novel features of construction and arrangement, as hereinafter described and claimed. v K m VThe more precise nature of my invention will be'better understood when described with reference to the accompanying drawings, in

whichv 5 Figure 1 is a side elevation of a bolt-threading appliance embodying my invention. Fig. 2 is acentral longitudinal section of the same; the structure being turned axially ninety degreesfrom the position shown in Fig. 1. Fig.

3 is an end elevation of the appliance with its' die-retaining cap in position; the direction of view being toward the cutting end of the ap- 5o pliance. Fig/l is an end elevation of the appliance .with its die-retaining cap removed; the direction of View being toward the cutting g senti No. 471,925. (no man.)

end of the appliance. Fig. 5 is a central longitudinal section of a modified form of bolt-` threading appliance embodying my inven-Y tion. Figj is a central longitudinal section of the modified structure; the appliance being turned axially ninety degrees from the position shown in Fig. 5. Fig.7is adetached view, in side elevation, of a tail-stock for hold- 6o ing the appliance shown in Figs. 5 and 6.

Referring rst to the structure shown in Figs. l to 4, both inclusive, l designates the stock of the bolt-tlireader, thisstock being of elongated tubular form, as to its bodyiportion, and having at its rear end a reduced tubular extension la which is designed to be connected to the tail-stock of a turret-lathe. The stock l of the appliance is designed to extend horizontally from the tail-stock of the 7o lathe, and the sides of its bodyportion are vformed with two oppositely disposed slots 11 each of whichris of straight form andextends longitudinally of the bodyportion of the stock.` ATlierear end of the stock 1, or that 75' end whichV is proximate to the extension la,

is externally screw-threaded to receive an adjust-ing-nut, the purpose of which will be presently fully explained, and the opposite or front end of the stock is diametrically en- 8o larged so as to form an external annular shoulder 1b; said enlarged end-portion being also radially recessed to form guides for the cutting-dies 2. Spiral springs 6 are interposed between the rear side of the shoulder l and the frontend of the body-portion of a sleeve 3 which surrounds the stock 1, so as to move both longitudinally and axially thereon; the I springs 6 serving to keep the sleeve 3 pressed rearward so that its rear end shall be in oon- 9o tact with the adjusting-nut 5 just referred to. At its front end, the sleeve 3 is formed with a forward extension 3?* the inner surface of which is formed with inclined sur faces 4t and radial recesses or cavities 15; 95 said inclined surfaces and recesses for cavities being alternated with each other, as is' most clearly shownin Fig. 4l. Within the stock l is located a cross-head or carrier l0 which extends transversely of the stock, and Ioo` which is of such length as to extend at its ends through the Islots 1,1 and also through two oppositely disposed spiral-like slot-s 12 formed in the corresponding sides of the sleeve 3. Midway of its length, the crosshead or carrier is formed with an inter- T nally screw-threaded opening 10fb through which is inserted a regulating-screw 13; said screw being externally screw-threaded and extending longitudinally ofthe stock 1, within the same. A retaining-screw 14 is shown as threaded longitudinally through one arm of the cross-head or carrier 10; the inner end of said retaining-screw impinging against the regulating-screw 13 and serving to fix the regulating-screw in any position to which it it may have been set in the cross-head orcarrier 10. There may either be four cuttingdies 2, as shown, or any other suitable number, arranged radially lwithin the front end of the stock 1 so that their outer ends shall come into contact with the inclined surfaces to'f 'the sleeve 3. The outer sides of these cuttingdies 2 are notched, as at 2a, to receive a circular spring 7 the, pressure of which serves to force the dies outward against the inclined surfaces 4,-and the dies and their springs are retained in proper' position by a cap 8 which lits closely over the front end of the sleeve 3.

.In using the appliance above described, the regulating-screw 13 is first turned axially in one direction or the other, so as to bring its front end a distance from the cutting-dies 2 'equal to the length of the screw-thread which is to be cut, and the adjusting-nut 5 is turned in one direction or the other, so as to ,bring the inner ends of the cutting-dies to such a distance from the axial center of the stock 1 as will accord with the thickness of the bolt minus the depth of the'th-read to be eut.`

The 'extension 1a is now fixed in the tailstock of a turret-lathe, and the bolt is fixed in the head-stock of said lathe so that the unheaded end of the bolt shall protrude inward between the cutting-dies 2. Power being now applied to the lathe, the bolt revolves axially While the appliance remains stationary, so far as any bodily axial movement is concerned.

As the bolt revolves, it draws the threadfcut-` ting appliance along bodily in 'a direction longitudinal of the bolt; the bolt entering the stock 1 and having the screw-thread cut thereon until the entering end of the bolt strikes the front end of the regulating-screw 13. Atthis moment the stock 1 and the sleeve 3 are drawn along over the cross-head or car- 'ri'er 10, and the stock lbeing prevented from turning axially by its straight longitudinal grooves 11, while the sleeve 13 is turned axially by the engagement of its spiral grooves 12 with the ends of the cross-head.`

This rotation of the sleeve 3 carries the inclined surfaces 4 on of the outer ends ofthe cutting-dies 2 and brings the intermediate recesses 15 into alignment with said outer ends of the dies; the spring 7 thereupon instantly throwing the dies 2 outward so that their outer ends shall enter the recesses 15, and automatically release the bolt from the dies without necessitating any immediate stoppage of the lathe. I have also shown the sleeve 3 as provided with a handle 16 which extends radially outward from vthe sleeve and by means of which an attendant can readily partially rotate the sleeve sufficiently to release the bolt whenever desired.

In Figs. 5 and 6 I have shown a modified form of thread-cutting appliance which also embodies the essential principles of my invention, but which differs from the structure shown in the preceding figures in that the appliance is connected to the tail-stock of the lathe by means of the sleeve of the appliance instead of by means of the stock of the appliance, as before, and also in that no regulating-screw 13 is used. In this instance, a tail-stock, such as is shown at 17 in Fig. 7, is used; said stock having two inwardly extending trunnions 1S Which enter two oppositely disposed and straightlongitudinal-slots 12a formed in the sleeve 3; two oppositely disposed spiral-like slots 11L being in this instance formed in the stock 1. As pre` Viously stated, no regulating-screw 13`is here used, suitable attachments of the usual or any preferred kind being used for arresting the motion of the lathe, and the handle 16a corresponding to the handle 16 being provided for the stock 3. In this instance, however, the'operation of the appliance is essentially the same as that previously described; the stock 1 and sleeve 3 rotatingwith relation to each other at the proper moment and the appliance continuing to act under the drawing action of the bolt until the desired length of thread has been cut, vas before.

Obviously many other minor modifications in construction and arrangement `may be adopted without departing from the essential principles of my invention.

In both of the structures above described,

provision is made for discharging the cuttings from the appliance; apertures 9 being formed through the side of the stock 1 and sleeve 3 for such purpose.

Having thus described myinvention, what IOO IIO

I claim as new therein, and desire to secure by v Letters Patent, is-

1. A bolt-threadin g appliance, comprising a stock or cutter-head and spring-pressed cutters therefor, a spring-pressed sleeve provided with inclines bearing against the cutters, and a nut movable upon the stock for moving the spring pressed sleeve, substantially as set forth.

2. A bolt-threading appliance, comprising a stock or cutter-head and spring-pressed cutters therefor, a spring-pressed sleeve provided with inclines bearing against the cutters, and also with recesses alternating with said inclines and designed to receive the cutters, and a nut movable upon the stock and serving to move the spring-pressed sleeve, substantially as set forth. v

3. A bolt-threading appliance, comprising a stock, spring-pressed cutters carried thereby, a spring-pressed sleeve provided with alter- ISO nated longitudinal inclines and radialrecesses for the cutters, and a nut movable'upon the stock and serving to move the spring-pressed sleeve, substantially as set forth.

4. A bolt-threading appliance, comprising the cutter-head .and its cutters, the sleeve provided with theE inclines. bearing against the backs of the cutters, a spring or springs for pressing the cutters against said inclines, la nut traveling on the head for moving the Vsleeve,and a spring or springs for holding the sleeve against said nut, substantially as set forth."- f

5. A bolt-threadin g appliance, comprising a stock carrying a plurality of radial cuttingdies, a sleeve embracing said stock and provided with alternated longitudinal inclines and radial recesses'to act upon and to receive said dies respectively, straight and curved slots for said stock and sleeve, a cross-head ywithin the stock and Working through said slots, and a regulating-screw threaded through said cross-head and located within the stock, substantially as set forth.

6.'Abolt-threadingappliance,comprisinga stock, :movable cutter-dies carried thereby, a sleeve both longitudinally and axially movableedirectly upon said stock, and means actuated by the bolt and automatically` producingthe axial movements of such sleeve, substantially as set forth. 1

7. Abolt-threadingappliance, comprising a stock, movable cutter-dies carried thereby,

ka sleeve longitudinally and axially movable uponhthe stock, a cross-head movable longitudinally within the stock and engaging straight and curved slots in the stockand sleeve respectively, and a regulating-screw movable in the lcross-Ahead and designed to be engaged by the bolt, substantially as set forth.

- LOUIS KIROHENBAUER.-

Witnesses:

TODD MASON, n O. R. BARNETT. 

